1. Field of the invention
This invention relates generally to the suppression systems and more particularly to a grease and dirt seal that will insure positive operation of the system.
2. Description of the relevant prior art
There are many forms and types of fire suppression systems, each system is designed to perform under a specific set of conditions. As a general rule most systems have the are suppression material located at a distance from the area protected. Sensors for the system are located in the area to be protected as are the suppression material dispensers.
In order to provide fail safe systems the sensors are often spring biased cables that contain fusible links which melt or other wise deteriorate and weaken in the presence of predetermined elevated temperatures. When the link or links separate the cable moves through tubing, which acts as a protective housing, and activates the fire suppression system.
The situation which occurs and is resolved by this invention is when the sensors are used in an area where there is an atmosphere with a high content of grease, dirt or paint in aerosol form. The situation typically arises over the deep fry cookers in commercial restaurants and in the spray booths of commercial paint shops. The air, drawn by evacuating blowers tends to have a uneven turbulent flow and as a result some of the particles are thrown aside and land on the walls of the range hood or paint spray booth for example. After a period of time, experience shows that a sufficient number of those particles could collect in the protective housing of the cable to inhibit the safe and quick operation of the fire suppression.
This invention adds a grease and dirt seal to the entrance of the tubing where the cable enters and exits within the contaminated atmosphere where the collection of particles is most likely to occur.
Examples of mechanical fusible links are shown in U.S. Pat. Nos. 3,779,004 issued Dec. 18, 1973 to Gloeckler who uses the link with a chain for controlling a weight release for a door closing or sprinkler system where two link elements are held against movement by a fusible temperature responsive retainer. U.S. Pat. No. 4,936,287 issued Jun. 26, 1990 to Hart et al. discloses a fusible link used with a ventilation system in a ceiling air diffuser were the fusible link would melt and close the butterfly valve and close off the supply of air to the room. U.S. Pat. No. 5,120,152 issued Jun. 9, 1992 to Gueli for a fusible link which consists of a pair of overlying plates adapted to engage a cable or other suitable device which are connected by a eutectic alloy selected to melt at a selected temperature and allow the plates to separate thereby allowing the connected system to function as designed.
The references taken alone or in combination or combined with what is common and well known to those skilled in the art fail to anticipate the invention disclosed and claimed herein.